Silly question

I am currently studying in Japan for a semester, and have to cook for myself. I am currently living in Yokohama, and my question is where can I find chili? More specifically, bird's eye chilis. I saw them when I was in the Chinatown here, but figured I would be able to find them in my area. Oddly, I can't. Is it just uncommon? My Japanese is not the greatest, so I decided I'd rather ask on the forum than try to ask shopkeepers.

Perhaps you can be more specific about where 'your area' is. Yokohama, although quite large, isn't that hard to get around and the Chinatown area in Kannai is pretty accessible. I would have thought that this was the perfect place to stock up on birds eye chilies.

Chili is being used more and more in Japanese homes but, from what I've seen and experienced, milder types are generally preferred. What you'll find in general food stores are Korean Chili flakes, rayu chili oil, yuzu kosho (a paste made from yuzu and chili), shichimi togarashi (or just shichimi) which is made of 7 spices, one of which is chili. Other foods also have it, for instance, there are often chili flakes in nuka meant for pickling and Korean kimchi is very popular. Occasionally there are fresh or dried chilies in local stores but this will depend on the store and its clientele.

But Yokohama IS a big city in its own right. To even have a chance of someone telling you about somewhere more local to you for chili you'd have to be more specific about where you're located.

If you are near Yokohama station station itself, perhaps you can try one of the large department stores in the fresh food section. Isn't there a big branch of Takashimaya there?

Ask for 'taka no tsume' (鷹の爪 たかのつめ）which is the closest widely available chili pepper to bird's eye. Use more or less according to how hot you want your dish to be. Adjusting recipes according to what is available locally is a skill you need to learn as an expat :)